a. Field of the Invention
This invention relates to pyrimidinyl-ureas which are useful as anti-allergic agents, and to their preparation.
B. Description of the Prior Art
Dyer et al., J. Org. Chem. 27, 982 (1962), show the preparation of 1-phenyl-3-(4-pyrimidinyl)urea, which alternatively can be named N-phenyl-N'-(4-pyrimidinyl)urea, by reacting 4-aminopyrimidine with phenyl isocyanate.
The Laboratories Leurquin French Demande (Patent Publication) 2,036,922, February 5, 1971 [Chem. Abstrs. 75, 118335q (1971)] relates to "2-(substituted ureido)-pyrimidines" of formula (1) ##STR1## "where R is H, alkyl, alkenyl, cycloalkyl or aryl, having cicatrizant, fatique lessening, sedative, anti-senescent and hypnotic sleep potentiating action". These compounds, except where R is H, were prepared "by treating 2-aminopyrimidine (2) with an isocyanate", e.g., (2) "was heated with PhNCO to give" (1) (R=Ph). A mixture of urea, 2-aminopyrimidine, and AcOH was kept at 0.5 hr. at 180.degree. to give (1) where R is H.